Revision 2.04 – September 7, 2007
405GPr – Power PC 405GPr Embedded Processor
Data Sheet
Strapping
When the SysReset input is driven low by an external device (system reset), the state of certain I/O pins is read to
enable default initial conditions prior to PPC405GPr start-up. The actual capture instant is the nearest SysClk edge
before the deassertion of reset. These pins must be strapped using external pull-up (logical 1) or pull-down
(logical 0) resistors to select the desired default conditions. The recommended pull-up is 3kΩ to +3.3V or 10kΩ to
+5V. The recommended pull-down is 1KΩ to GND. These pins are use for strap functions only during reset. They
are used for other signals during normal operation. The following tables list the strapping pins along with their
functions and strapping options. The signal names assigned to the pins for normal operation follow the pin
number.
The PPC405GPr can be used as a replacement for the PPC405GP. When the PPC405GPr is used for this
purpose, it should be strapped to operate in the PPC405GPr Legacy Mode. This option is selected by strapping
ball D20 (GPIO24) low (0). If Legacy Mode is selected, the “PPC405GPr Legacy Mode Strapping Pin Assignments”
table should be used to determine the strapping options. To operate the chip as a PPC405GPr, strap D20
(GPIO24) high (1) and use “PPC405GPr New Mode Strapping Pin Assignments” on page 53 to determine the
strapping options.
PPC405GPr Legacy Mode Strapping Pin Assignments (Sheet 1 of 2)
Function
Option
Ball Strapping
PLL Tuning 1
AF3
AF2
AD16
UART0_Tx
UART0_DTR
UART0_RTS
for 6 ≤ M ≤ 7 use choice 3
for 7 < M ≤ 12 use choice 5
for 12 < M ≤ 32 use choice 6
Choice 1; TUNE[9:0] = 1010111100
Choice 2; TUNE[9:0] = 0100111000
Choice 3; TUNE[9:0] = 0100110110
Choice 4; TUNE[9:0] = 0100111100
Choice 5; TUNE[9:0] = 0100111000
Choice 6; TUNE[9:0] = 1000111100
Choice 7; TUNE[9:0] = 1000111110
Choice 8; TUNE[9:0] = 1011111110
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
PLL Forward Divider 2
PLL Feedback Divider 2
PLB Divider from CPU 2
D16
B15
DMAAck0
DMAAck1
Bypass mode
Divide by 3
Divide by 4
Divide by 6
0
0
1
1
0
1
0
1
B14
DMAAck2
C12
DMAAck3
Divide by 1
Divide by 2
Divide by 3
Divide by 4
0
0
1
1
0
1
0
1
P25
EMCTxD3
L24
EMCTxD2
Divide by 1
Divide by 2
Divide by 3
Divide by 4
0
0
1
1
0
1
0
1
AMCC
51
AMCC [ APPLIED MICRO CIRCUITS CORPORATION ]
